But last month, Moscow threw its weight behind Mr. Annan's plan to end the year-long uprising, which has killed more than 9,000 people by UN estimates. It called for a withdrawal of all government forces from Syrian towns and cities, followed by a shaky cease-fire that went into effect last Thursday and appears to be just barely holding despite multiple violations alleged on both sides.

Speaking in televised remarks today, Russian Foreign Minister Sergei Lavrov implied that the shoe is on the other foot now, with Moscow strongly backing the UN peace plan for Syria and willing to hold both Mr. Assad and his opponents to task but, he alleged, the effort is being undermined by unnamed Western and Arab countries.

"There are those who want Kofi Annan's plan to fail," Mr. Lavrov insisted. "Today, those who from the beginning foretold the failure of Annan's plan are doing a lot to see to it that this prophecy comes true… They are doing this by delivering arms to the Syrian opposition and stimulating the activity of rebels who continue to attack both government facilities and civilian facilities on a daily basis."

The cease-fire remains "quite fragile" because of the reluctance of those outside forces to fully back the Annan plan, Lavrov suggested, although he added that Assad bears a share of blame for the continuing uncertainty. "Of course, government forces are also taking measures to react to such provocations, and as a result it is not all going very smoothly yet," he said.

Analysts say that Lavrov is making the most of Moscow's recent shift away from months of single-minded support for the Assad regime and its apparently sincere embrace of the Annan plan.

"This is an unaccustomed place for Lavrov to find himself, unambiguously on the side of peace and reason in Syria," says Alexander Konovalov, president of the independent Institute for Stategic Assessments in Moscow.

"But, in fact, he's got a point. The Annan plan needs to be supported, if only because it is the only plan out there. If other forces aren't getting on board, and are indeed covertly fanning the flames of civil war as Lavrov alleges, then they and their backers will be to blame if the whole thing collapses. After months of being accused of obstructionism, this looks much better for Russia," Mr. Konovalov adds.

Lavrov received a cautious vote of support from visiting members of the Syrian opposition today, who praised Russia for distancing itself from the Assad regime but urged it to do more to promote genuine democratic reforms in Syria.

"The representatives of the Russian government aren't inclined to support the idea of preservation of the dictatorial regime," Haytham Manna, spokesman for the Arab Commission for Human Rights, told a Moscow press conference today. "They are talking about the need for continuing democratic changes, and that's very important for us… Russia has all the necessary levers to apply pressure on Assad's government and help Annan's mission."

Abdul-Aziz al-Kheir, head of the National Coordination Body for Democratic Change in Syria, which opposes armed insurrection, agreed that Moscow's stance on Syria has been changing rapidly over recent weeks.

"[The Annan plan] is the last chance to end the fratricidal massacre and create preconditions for the transfer to a democratic form of government," he told the press conference.

Some Russian experts say that changing conditions in Syria, where Assad's military forces have gained the upper hand in recent weeks, are the main reason that Moscow's diplomatic hand appears to be strengthening.

"Until last week the West's preference was for a victory of the rebels at any price, but now there's a lot less enthusiasm for that," says Dmitry Babich, an expert with the official RIA-Novosti agency in Moscow. "This happened mainly because the rebels failed to seize any big cities and because of Assad's military success. So if the tables have turned, it hasn't been done by Russia.

"Actually, Russia's position hasn't changed much," Mr. Babich adds. "Moscow was never a passionate fan of Assad, and wasn't ready to do anything to save him, but it was alarmed at the idea of any more precedents that would license massive outside interference into the affairs of a sovereign country."

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